After install, when trying to run nikto-2.1.5, it fails out with the following error: "Undefined subroutine &LW2::init_ssl_engine called at /usr/bin/nikto line 66." This might be related to bug 533900 and/or bug 521884.
I found a workaround posted at http://gentoo.org.in/nikto-ssl-error-fix/ to comment out the offending line. This disables SSL support, but allows nikto to run regular HTTP checks. HTH.
Please retry with nikto-2.1.6_p20180122